Machine Type Communication (MTC), also referred to as Machine to Machine (M2M), is currently a main form of application of the Internet of Things (IoT) technology. Currently available MTC devices are mainly based on Global System of Mobile communication (GSM) system. Recently, more and more mobile operators have chosen Long Term Evolution (LTE)/Long Term Evolution Advanced (LTE-A) as evolutions towards further broadband wireless communication systems due to their high spectral efficiency. Various MTC data services based on LTE/LTE-A will be more attractive.
In the 3rd Generation Partnership Project (3GPP) Technical Report (TR) 45.820 V200, several techniques applicable to Comb-Internet of Things (C-IoT) have been disclosed, among which Narrow Band-Internet of Things (NB-IoT) is the most attractive one. The NB-IoT system has a system bandwidth of 200 kHz, which is the same as the channel bandwidth of the GSM system. This makes it very convenient for the NB-IoT system to reuse GSM spectrums and reduce interference with neighboring GSM channels.
For an IoT User Equipment (UE), currently only transmission of Physical Uplink Shared Channel (PUSCH) is supported in the uplink. Both single-tone and multi-tone PUSCH transmissions can be supported. There is currently no effective solution to the problem associated with PUSCH resource allocation.